Iron Measured in Nasal Exudate Samples as a New and Useful Biomarker in the Differential Diagnosis of Patients with Acute Stroke

Cerebrovasc Dis. 2020;49(6):625-631. doi: 10.1159/000511395. Epub 2020 Nov 20.

Abstract

Introduction: Differential diagnosis between ischemic and hemorrhagic strokes in the acute stage is one of the major challenges of neurovascular research. Several biomarkers have been studied, but attempts to date have focused on determining their blood levels. Recently, cerebral lymphatic drainage toward the nostrils has been discovered, giving us the chance to study nasal exudate looking for biomarkers of neural damage. We sought to confirm whether iron levels in nasal exudate could identify the hemorrhagic nature of acute stroke.

Methods: We studied iron nasal exudate levels in 32 ischemic and 43 hemorrhagic stroke patients. All patients underwent neurological examination assessed by the National Institutes of Health Stroke Scale (NIHSS), brain computed tomography to the differential diagnosis of stroke subtype, laboratory tests, and measurement of iron levels in nasal exudate.

Results: The iron levels in nasal exudate were higher in hemorrhagic stroke patients. The area under the receiver operating characteristic curve for ischemic/hemorrhagic stroke discrimination was 0.896 (95% confidence interval 0.823-0.970) and cutoff point of 0.078 nmol/mg (sensitivity 93%, specificity 73%).

Conclusions: Our findings suggest that iron levels in nasal exudate may be useful in the acute stage for the differential diagnosis between ischemic and hemorrhagic damage in acute stroke patients. They also open a potential field to study other biomarkers in nasal exudate in several neurological disorders. Clinical studies must be performed to confirm our results.

Keywords: Brain lymphatic drainage; Differential diagnosis; Iron; Stroke.

Publication types

  • Comparative Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Biomarkers / analysis
  • Diagnosis, Differential
  • Exudates and Transudates / chemistry*
  • Female
  • Hemorrhagic Stroke / diagnosis*
  • Hemorrhagic Stroke / metabolism
  • Humans
  • Iron / analysis*
  • Ischemic Stroke / diagnosis*
  • Ischemic Stroke / metabolism
  • Lymph / chemistry*
  • Male
  • Middle Aged
  • Nose
  • Predictive Value of Tests
  • Proof of Concept Study
  • Prospective Studies
  • Reproducibility of Results

Substances

  • Biomarkers
  • Iron